Selecting Object(s) produces null

I just wrote a script that worked well for one object. I set it up for Dynamo Player, exited Dynamo and used the Player four times. One of the times I didn’t get the result I expected, so clicked on View Graph in Dynamo to see what’s up. Ever since then, I can’t select an object. The four character object code changes if I select something different, but the output is always null. Even if I go the other route of selecting all by type, or selecting all on layer. Null. Restarted computer, closed C3D and come back, created a new drawing. Null. Tried a different script. Null. Change to Select Objects node. Shows two object codes, but…Null output.

Any tips?

C3D crashed shortly after, and the script worked again…Until I tried something new, same issue, so I deleted everything from the %temp% folder and currently working as expected.

Which version of Civil 3D?
Does it happen often, or just this one time?
Only on your PC, or others too?

C3D 25.2.1 - C3D 26 is installed, but not being used
First time experiencing it, no recent updates
Haven’t tried on another computer yet
I’ve since cleaned up my code, so not getting it to repeat might now be related to that.